Above the village of Kypseli rises one of the largest and most striking lava domes of the Methana peninsula. The Kosona lava dome belongs to a series of volcanoes, which evidently developed on a fault. At its southern foot lie the mofettes of Thiafi. Maybe they still have a contact with the magma chamber of the volcano? On its hillside there are several places where you can find pumice. Whether this pumice comes from this volcano or the ancient caldera, must show even more detailed geological research.